Why Students Fail IMAT Physics (And How to Fix It)

Most students who lose marks on IMAT physics know the physics. That's what makes this section so frustrating, and it's why "revise harder" doesn't work. 

The IMAT physics section is thirteen questions out of sixty (Q48–60 on the 2025 paper). It is not testing whether you can do physics. It's testing whether you read the question — and the wrong answer you're about to give is usually printed on the paper as an option, on purpose. Here are five real examples, worked, with the answers verified against the official keys.

 Trap 1: "From the surface" is not "from the centre"

IMAT 2025, Question 58. An astronaut takes a spacewalk at a distance from the Earth's surface equal to three times the Earth's radius. What fraction of g does she experience?

You know gravity falls off as 1/r². Three radii out, square the three, answer g/9. It's option C, sitting right there.

 It's wrong.

 The question says three radii from the surface. And r in Newton's law is measured from the centre. So r = R + 3R = 4R, and the answer is 1/4² = g/16 — option D. The physics took four seconds. The mark was decided by one word. And g/9 was pre-loaded as an option because the examiner knew exactly which one you'd reach for.

 The fix: underline every adjective and every prepositional phrase before you calculate. From the surface. Perfectly insulating. Isothermal. They are never decoration.

 Trap 2: Constant speed does not mean zero force 

IMAT 2025, Question 59. A 2,000 kg car travels at a constant 15 m/s. Friction is 2,000 N. At t = 0 it accelerates at 2.0 m/s². What are the engine forces before and after?

Two traps stacked on top of each other.

First: "constant speed, so no force." Options D and E both offer you F₁ = 0. But constant speed means zero net force, not zero engine force. Friction is pulling back with 2,000 N the whole time. If the engine gave nothing, the car would slow down. It doesn't. So the engine is supplying exactly 2,000 N — cancelling friction, not sitting idle. F₁ = 2,000 N.

Second: ma = 2,000 × 2.0 = 4,000 N, so F₂ = 4,000? That's option D, and it's also wrong. 4,000 N is the net force required. Friction hasn't gone anywhere. The engine has to pay 2,000 N to friction and 4,000 N to accelerate. F₂ = 6,000 N. Option C.

 And the 15 m/s? Never used. Not once. It's there to make you feel like you've missed a step.

 The fix: draw the free-body diagram. Two arrows. Ten seconds. It makes both traps visible immediately.

Trap 3: Speed is not velocity — and they ask it twice

IMAT 2023, Question 59. A vehicle travels east 6 km, then south 8 km, in 15 minutes. What is the magnitude of the average velocity?

6 + 8 = 14 km. Over a quarter of an hour, that's 56 km/h. Option C. Done.

That's average speed. They asked for average velocity.

Velocity uses displacement, not distance. East 6, south 8 is a right angle, so displacement is the hypotenuse: √(36 + 64) = 10 km. A 3-4-5 triangle, scaled. 10 km over a quarter hour = 40 km/h. Option A.

Now look at the rest of the options. 56 is speed. 14 is the distance with no time at all. 8 is one leg of the triangle. Every wrong answer on that list is a specific mistake somebody made, printed on the paper deliberately.

And they ask it again in a completely different subject. IMAT 2024, Question 58 gives you an electron entering a magnetic field and asks which statement is FALSE. Four options are formulas — cyclotron radius, period, frequency, angular velocity — and all four are correct. The fifth is a plain sentence: "the electron continues to move with a constant velocity v."

 And it's almost true. The electron's speed genuinely is constant — magnetic force is always perpendicular to motion, so it does zero work. But velocity is a vector, the electron is moving in a circle, so its direction changes continuously and therefore so does its velocity. D is false. D is the answer. The examiner hid it in the only option without maths in it, knowing you'd burn ninety seconds verifying three formulas that were never wrong.

The fix: speed is a number. Velocity is a number and a direction. Say it out loud once and you'll never lose either of these marks again.

Trap 4: You cannot halve a temperature in Celsius

IMAT 2023, Question 57. An ideal gas at 25°C expands isothermally. The piston is then fixed and the gas is cooled until the pressure halves. Final temperature, to the nearest degree Celsius?

Pressure halves, so temperature halves: 25 ÷ 2 = 12.5 ≈ 13°C. Option B. Clean, fast, wrong.

Celsius is not an absolute scale. 0°C isn't zero thermal energy — it's just where water happens to freeze. Halving a Celsius number is a meaningless operation.

25°C = 298 K. Halve it → 149 K. Convert back → −124°C. Option A.

Two more things they planted: the isothermal expansion is a decoy (isothermal means the temperature didn't change, and the volume never comes back). And option D is −149°C, for anyone who reached 149 K and forgot to convert back. Every wrong answer is a checkpoint you might have fallen off.

The fix: the moment any gas law appears, convert to Kelvin before you do anything else. Before you even finish reading the question.

Trap 5: Knowing more physics can make you worse

IMAT 2023, Question 60. Two perfectly insulating spheres, charges Q₁ and Q₂, radii R₁ and R₂, are placed in contact. What is the charge on the first sphere now?

Option D is (Q₁R₁ + Q₂R₂)/(R₁ + R₂). That's a real formula. It's in your textbook. It's correct — for conducting spheres.

These are insulating. Charge cannot move through an insulator. You touch them together and precisely nothing happens. Q₁ stays Q₁. Option A. There is no calculation in this question at all. Here's the part that should worry you: the better you know electrostatics, the more likely you are to recognise D and take it. Your knowledge actively hurt you. Only reading saved you.

The fix: the radii were given to bait you into reaching for the formula. When a question hands you numbers, ask what they're for before you use them.

The pattern underneath all five

The IMAT reuses its traps. Not its questions, its traps. Surface versus centre. Celsius versus Kelvin. Speed versus velocity. Distance versus displacement. The same handful of ideas, in different costumes, year after year.

 Which means the physics section is largely predictable, and "revise harder" is the wrong response to it. You don't have a knowledge problem. You have a reading problem wearing a physics costume. Three habits fix most of it:

1. Underline every adjective and prepositional phrase before you calculate.

2. Draw the diagram — free-body, or the geometry, or the curve. Always.

3. Ask what each number is for. Some of them are for nothing.

Want to check where you actually stand?

Every paper referenced above is free, just click here to have them all.

And if you want to know whether you're losing marks to knowledge or to reading the Free Diagnostic Test will tell you in about 30 minutes. It's almost always reading.

If it turns out to be technique, that's what our Intensive Course is for: three weeks, live, maximum ten students, everyone answers out loud.

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Alex — medicine student at Sapienza University, Rome. Scored top 20 in Europe on the IMAT. Every answer above has been worked by hand and cross-checked against the official answer keys.